After surveying over 4,000 people, Deloitte, the advisory network, and GfK, the insights provider, found nearly 24% used devices like laptops, smartphones and tablets when in front of the TV.
More specifically, 20% of 16–24 year olds "frequently" used messaging services, email and social media to discuss programmes they were watching on television, and 20% "sometimes" did so.
By contrast, 79% of respondents aged 55 years old or above "never" participated in this activity, indicating the general early adopter status of young consumers very much applied in this area.
Elsewhere, only one in ten contributors had looked online for information about broadcast content they were currently viewing, suggesting limited "second screen" engagement levels.
"Browsing while watching television typically means flitting between a preferred set of websites, often comprising news, sports, ecommerce," said Paul Lee, Deloitte's director of technology, media and telecommunications research.
"Time spent on these may be a substitute for reading newspapers and magazines, or looking through catalogues."
Although 40% of the viewers who "connected" with TV programmes online liked being able to send in their comments to live shows, a further 68% did not want the website for the goods or ads appearning on TV to automatically load on digital devices.
"Second screening's impact is far greater in driving conversations about a programme, as opposed to interaction with it," said Lee.
"Second screening may well end up with a similar status as eating in front of the TV: an everyday experience for some; absolutely unthinkable for others. One thing is certain: it is here for good."
Media companies may face a "predicament" as a consequence of this shift, the analysis added, as allocating resources to "second screen" material will improve the consumer experience, but without guaranteed results.
"Every pound spent on second screen content may be a pound diverted from the first screen; in order to justify the investment content creators need to get the balance right between all screens," said Lee.
Data sourced from Deloitte; additional content by Warc staff